Article

Predator odor modulates auditory event-related potentials in mice

SMRI Laboratory for Experimental Therapeutics in Psychiatry, Department of Psychiatry, University of Pennsylvania, Philadelphia 19104, USA.
Neuroreport (Impact Factor: 1.52). 08/2009; 20(14):1260-4. DOI: 10.1097/WNR.0b013e3283300cde
Source: PubMed

ABSTRACT

Animals process information from different sensory modalities, requiring integration of signals and assignment of significance. People with schizophrenia perceive sensory information without external stimuli (hallucinations) and attribute meaning to coincidental events (referential delusions), suggesting deficits in sensory integration. We investigate sensory integration deficits by measuring the impact of olfactory cues on auditory processing in a mouse model of schizophrenia. N-methyl-D-aspartate-NR1 knockdown and wild-type mice were exposed to predator odor during auditory event-related potentials. Both groups reduced N1 event-related potential amplitude in the presence of predator odor, indicating that mice appropriately integrate olfactory and auditory stimuli. NR1 knockdown mice do not have deficits in this task, suggesting that sensory integration may rely on non-N-methyl-D-aspartate receptor mediated circuits.

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    • "For example, in canaries and zebra finches, neurons in the caudomedial nidopallium, a secondary auditory region, can be tuned to the vocalizations of bird species composing a social group (Terleph et al., 2008). In mice, cues indicating the presence of a predator decrease auditory event-related potentials, which may influence how mice respond to the threat of predators (Halene et al., 2009). "
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    • "Here, we demonstrate that auditory function, exploratory ability, and the capacity to vocalize are all intact. Likewise, we and others have previously reported that visual and olfactory function is unaltered in NR1 neo−/− mice, using behavioral and electrophysiological measures (Duncan et al., 2004, Halene et al., 2009b). Pain sensation was shown to be present, and perhaps even enhanced, in a previous study (Bickel et al., 2007). "
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    • "However, integration of visual or auditory information with olfactory cues remains largely unstudied. Although evidence for multisensory integration between olfaction and audition is scarce, it is not without precedent (Halene et al., 2009). In addition, recent work showed that the opposite interaction also exists. "
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